Novel nitric oxide-releasing amidine- and enamine-derived diazeniumdiolates, compositions and uses thereof and method of making same

ABSTRACT

The present invention relates to nitric oxide-releasing amidine- and enamine-derived diazeniumdiolates, compositions comprising such compounds, methods of using such compounds and compositions, and to a method for the preparation of nitric oxide-releasing amidine- and enamine-derived diazeniumdiolates via the direct reaction of nitric oxide with amidines and enamines, and to a method of converting amines into such compounds.

FIELD OF THE INVENTION

[0001] The present invention relates to nitric oxide-releasing amidine-and enamine-derived diazeniumdiolates, to compositions comprising suchcompounds, to methods of using such compounds and compositions, to amethod for the preparation of nitric oxide-releasing amidine- andenamine-derived diazeniumdiolates via the direct reaction of nitricoxide with amidines and enamines, and to a method of converting amine'sinto such compounds.

BACKGROUND OF THE INVENTION

[0002] Nitric oxide (NO) has been implicated as part of a cascade ofinteracting agents involved in a wide variety of bioregulatoryprocesses, including the physiological control of blood pressure,macrophage-induced cytostasis and cytotoxicity, and neurotransmission(Moncada et al., “Nitric Oxide from L-Arginine: A BioregulatorySystem,”. Excerpta Medica, International. Congress Series 897, ElsevierScience Publishers B. V.: Amsterdam (1990); Marletta et al., Biofactors2: 219-225 (1990); Ignarro, Hypertension (Dallas) 16: 477-483 (1990);Kerwin et al., J. Med. Chem. 38: 4343-4362 (1995); and Anggard, Lancet343: 1199-1206 (1994)). Given that NO plays a role in such a widevariety of bioregulatory processes, great effort has been expended todevelop compounds capable of releasing NO. Some of these compounds arecapable of releasing NO spontaneously, e.g., by hydrolysis in aqueousmedia, whereas others are capable of releasing NO upon being metabolized(Lefer et al., Drugs Future 19: 665-672 (1994)).

[0003] Keefer et al. (U.S. Pat. Nos. 4,954,526; 5,039,705; 5,155,137;5,208,233 and 5,405,919 and related patents and patent applications, allof which are incorporated herein by reference) disclose, among others,the use of certain nucleophile/nitric oxide adducts as NO-releasingagents, i.e.,

[0004] in which the nucleophilic residue (Nuc) is a primary amine, asecondary amine or a polyamine. Although such adducts offer manyadvantages over other currently available nitric oxide-releasingcompounds, one disadvantage presented by the use of such adducts aspharmaceutical agents is the potential risk of release of nitrosamines,which are carcinogenic, upon decomposition and release of NO. Anotherdisadvantage of the adducts of primary amines is that they can beunstable even as solids due to a tendency to form traces of potentiallyexplosive diazotates.

[0005] Several types of compounds of the general structure

[0006] have been known for many years. Traube (Liebigs Ann. Chem; 300:81-123 (1898)) reported the preparation of a number of such compoundsand noted that treatment of the compounds with acid produced a “browngas.” Although brown gas suggests the release of NO, given that a browngas also may be produced in the disproportionation of nitrite, therelease of brown gas by the compounds prepared by Traube is not, in andof itself, evidence of NO release. Compounds of the structural typereported by Traube are known to require harsh treatment with mineralacids to release any gas which is, of course, incompatible with abiological utility.

[0007] Another compound, which has the structure

[0008] and which has been named cupferron, has been shown by Kubrina etal., Izvestia Akademii Nauk SSSR Seriia Biologicheskaia 6: 844-850(1988)) to generate NO in vivo. In addition, the antibiotics alanosine(C(O)(OH)CH(NH₂)CH₂N(O)═NOH) and dopastin (CH₃CH═CHC(O)NHCH₂CH(i-propyl)-N(O)═NOH), as well as cupferron, have been shown to releaseNO in vivo by enzymatic oxidation (Alston et al., J. Biol. Chem. 260:4069-4074 (1985)).

[0009] More recently, Keefer et al., in U.S. Pat. No. 5,212,204, havebroadly described that an organic moiety may be linked via carbon to theN₂O₂ ⁻ group. This patent does not disclose an amidine or enaminestructure as the nucleophile, nor does it teach the nature of thestructural characteristics that an organic moiety must possess to causethe resulting N₂O₂ ⁻ group to be a nitric oxide donor.

[0010] Some N₂O₂ ⁻-containing compounds have been disclosed to be usefulas curing agents in rubber manufacture, antiknock additives forgasoline, indicator dyes, explosives, corrosion inhibitors andfungicides (Danzig et al., U.S. Pat. No. 3,309,373; Wiersdorff et al.,Chem Abstracts 77: 48034f (1972); Massengale, U.S. Pat. No. 2,635,978;and Metzger et al., U.S. Pat. No. 2,954,314). However, the mechanism ofthe reported action of these compounds was not described.

[0011] In this regard, a recent study of the N₂O₂ ⁻ group (Taylor etal., J. Org. Chem. 60: 435-444 (1995)) proposed a mechanism for theobserved NO release. The proposed mechanism was based on quantummechanical calculations which showed protonation at the terminal oxygento be most favored thermodynamically in the case of N bound N₂O₂ ⁻.

[0012] None of the above disclosures, however, mention anything aboutthe release of nitroxyl (HNO, which, at the physiological pH of 7.4,exists as NO⁻) by this functional group. Recent results suggest that,under certain conditions, many classes of “NO donors” may release someNO⁻ (see the discussions for nitrosothiols and diazeniumdiolates as wellas the table of NO donors in Feelisch et al., Donors of Nitrogen Oxides,In Methods in Nitric Oxide Research, M. Feelisch and J. S. Stamler,Eds., Ch. 7, pp. 71-115, John Wiley and Sons, New York (1996)).

[0013] To date, there are three compounds used to generate HNO insolution. One compound, Angeli's salt, which is the standard HNO source(Fukuto et al., J. Pharm. Exp. Ther. 263: 546-551 (1992)), is, ofcourse, an inorganic salt. The other two compounds, acetylated Piloty'sacid (Smith et al., J. Amer. Chem. Soc. 82: 5731-5740 (1960)) andbenzoylated hydroxycyanamide (Lee et al., J. Med. Chem. 35 3648-3652(1992)) are promising inhibitors of aldehyde dehydrogenase. However,even in these compounds, there is debate as to whether the observedphysiological effects are attributed to NO, or to NO⁻. For example,Piloty's acid has been shown to release NO oxidatively underphysiological conditions (Zamora et al., Biochem. J. 312: 333-339(1995)).

[0014] Reports that superoxide dismutase can prolong the effects of NOvia its reversible reduction to NO⁻ (Murphy et al., PNAS USA 88:10860-10864 (1991)) and that NO⁻, itself, exhibits potent activity as avasodilator (Fukuto et al., J. Pharm. Exp. Ther. 263: 546-551 (1992).)and as an inhibitor of aldehyde dehydrogenase (Lee et al., J. Med. Chem.35: 3648-3652 (1992)) suggest that compounds, which release either NO orNO⁻ or mixtures of the two, are potentially useful pharmaceutical agentsand may even offer advantages over compounds that just release NO.

[0015] Despite the extensive literature available on NO and nitricoxide-releasing compounds, there remains a need for stable nitricoxide-releasing compounds in which the nitric oxide-releasing group N₂O₂⁻ is bonded directly to a carbon atom and which can be prepared fromcompounds that do not include a nitrogen atom suitable for conversion toa diazeniumdiolate.

[0016] Accordingly, it is an object of the present invention to providea chemical structural framework having an atomic and electronicarrangement such that an N₂O₂ ⁻ functional group attached thereto willserve as a spontaneous. NO and/or NO⁻ donor. It is a further object ofthe present invention to provide a method for producing novel NO and/orNO⁻-releasing diazeniumdiolates in which the N₂O₂ ⁻ group is bound to acarbon atom. Another object of the present invention is to provide NO-and/or NO⁻-releasing derivatives of amidines and enamines. A relatedobject of the present invention is to provide NO- and/or NO⁻-releasingderivatives of known pharmaceutical agents; A more specific object is toprovide NO- and/or NO⁻-releasing derivatives of known pharmaceuticalagents whose nitrogen atoms do not provide suitable N-diazeniumdiolatesas nitric oxide donors. Yet another object of the present invention isto provide compositions comprising NO- and/or NO⁻-releasing derivativesof amidines and enamines. A further object of the present invention isto provide methods of using NO- and/or NO⁻-releasing derivatives ofamidine and enamine compounds, and compositions thereof. These and otherobjects of the present invention, as well as additional inventivefeatures, will be apparent from the description of the inventionprovided herein.

BRIEF SUMMARY OF THE INVENTION

[0017] The present invention provides NO- or NO⁻-releasingdiazeniumdiolates which are derived from an enamine or an amidine and inwhich the N₂O₂ ⁻ functional group is bonded to a carbon atom. Thepresent invention also provides compositions comprising suchdiazeniumdiolate compounds, and methods of using such compounds andcompositions. The present invention further provides a method ofproducing an NO- or NO⁻-releasing enamine- or amidine-deriveddiazeniumdiolate. Additionally, the present invention provides a methodfor the preparation of an NO- and/or NO⁻-releasing amidine derivativefrom an existing amino compound. The method comprises reaction of theamino compound with an acetamidating reagent followed by reaction withnitric oxide gas.

DETAILED DESCRIPTION OF THE INVENTION

[0018] In accordance with one aspect of the invention, there is provideda novel class of nitric oxide-nucleophile adducts or diazeniumdiolateshaving an amidine- or enamine-derived chemical linkage in which the N₂O₂⁻ functionality is bound directly to a carbon atom of the linkage. Theamidine- or enamine-derived chemical linkage which includes the N₂O₂ ⁻functional group is represented by the schematic formula depicting thecharacteristic connectivity:

[0019] wherein

[0020] C²˜C³ means either C²-C³ or C²═C³

[0021] m is 1 or 2

[0022] q is 0 or 1

[0023] p is 0 or 1

[0024] provided that

[0025] (1) C² is tetravalent, and bound to two or more of C¹, C³, N¹ andN²;

[0026] (2) when p=1, then q=0 and C²˜C³ means C²˜C³; or

[0027] (3) when p=0, and q=1, then C²˜C³ means either (i) C²═C³ or (ii)C²-C³ where C²˜N¹ means C²═N¹;

[0028] (4) when C²˜C³ means C²-C³ and q=1 and p=0

[0029] C²˜N¹ and C²˜N² means

[0030] It will be appreciated by those skilled in the art that due tothe nature of the synthesis reaction employed as disclosed herein, thedouble bond in all cases would originally form as a C═N and thentautomerize if that is possible due to the presence of a C—H β to N. Thedouble bond typically tautomerizes to the more thermodynamically favoredstructure. However, less thermodynamically favored tautomers may occurand have been observed depending on conditions such as solvent or thelike. In compounds where there is no H in the β position to N¹ notautomerization occurs. Thus, the present invention contemplates allNO-releasing diazeniumdiolates which include an amidine- or anenamine-derived chemical linkage in which the N₂O₂ ⁻ functional group isbound to a carbon atom irrespective of the tautomer that isthermodynamically favored. The electron movement or tautomerization forthe enamines and for the amidines is the same conceptually, but in thecase of the enamines it is the lone pair of electrons associated withthe nitrogen atom which must be used in the reaction since there is no Hon the enamine nitrogen.

[0031] The amidine- and enamine-based diazeniumdiolates of the presentinvention are advantageous in several respects. These compounds are notexpected to decompose to carcinogenic nitrosamines. Thediazeniumdiolates of the present invention exhibit the full range ofwater solubility. Some of the diazeniumdiolates of the present inventionare thus particularly useful where water insolubility is desirable, suchas in stents, implants, prostheses and the like. Many diazeniumdiolatesof the present invention are characterized by long-term slow release ofNO and can be used in coatings or the like. Further, these compounds donot bleed out of the coating, even after the NO has been released. Thediazeniumdiolates of the present invention are very stable-solids and insolution are more heat stable than the previously described nitrogenanalogs. Some can be recrystallized from boiling solvents withoutdecomposition.

[0032] In keeping with the invention, the amidine-deriveddiazeniumdiolates may be further described in accordance with thefollowing formulas:

[0033] wherein R¹-R⁵ can be a wide variety of substituents withoutdeparting from the scope of the present invention owing to the fact thatany compound which includes the characteristics of the chemical linkageidentified above is contemplated herein.

[0034] Thus, in the compounds of Formula I, II or III, R¹-R³ areindependently chosen from hydrogen, an unsubstituted or substitutedC₁₋₁₂ straight chain alkyl, an unsubstituted or substituted C₃₋₁₂branched chain alkyl, an unsubstituted or substituted C₃₋₁₂ straightchain olefinic, an unsubstituted or substituted C₃₋₁₂ branched chainolefinic, a substituted or unsubstituted C₃₋₁₂ cycloalkyl, a C₃₋₈heterocyclic ring bound through a carbon atom and in which-theheteroatom is oxygen or nitrogen, a substituted or unsubstitutednaphthyl, a substituted or unsubstituted tetrahydronaphthyl, asubstituted or unsubstituted octrahydronaphthyl, benzyl or substitutedbenzyl, substituted with-up-to three substituents, or a substituted orunsubstituted phenyl, substituted with-up to three substituents.

[0035] In the compounds of Formula I, II or III, R⁴ and R⁵ areindependently hydrogen, an unsubstituted or substituted C₁₋₁₂ straightchain alkyl, an unsubstituted or substituted C₃₋₁₂ branched chain alkyl,an unsubstituted or substituted C₃₋₁₂ straight chain olefinic, anunsubstituted or substituted C₃₋₁₂ branched chain olefinic, asubstituted or unsubstituted benzyl, a substituted or unsubstitutedphenyl, a substituted or unsubstituted piperazino, or a substituted orunsubstituted morpholino. R⁴ and R⁵ also can be amino, an unsubstitutedor substituted alkylamino, carboxyalkylamino, carboxydialkylamino, anunsubstituted or substituted tolyl, xylyl, anisyl, mesityl, nitro, anunsubstituted or substituted arylamino, an unsubstituted or substituteddialkylamino, an unsubstituted or substituted diarylamino, anunsubstituted or substituted acetyl, an unsubstituted or substitutedacetoxy, carboxy, an unsubstituted or substituted carboxyalkyl, such asan unsubstituted or substituted carboxymethyl or an unsubstituted orsubstituted carboxyethyl, an unsubstituted or substituted alkylcarbonyl,thiol, an unsubstituted or substituted alkylthio, an unsubstituted orsubstituted alkoxy, carboxamido, an unsubstituted or substitutedalkylcarboxamido, an unsubstituted or substituted dialkylcarboxamido, anunsubstituted or substituted phenoxy, an unsubstituted or substitutedbenzyloxy, an unsubstituted or substituted nitrophenyl, phenylcarbonyl,benzylcarbonyl, trialkylsilyl.

[0036] When any of the groups indicated above for R¹-R⁵ are identifiedas being substituted, such as when the C₁₋₁₂ straight chain alkyl, theC₃₋₁₂ branched chain alkyl, the C₃₋₁₂ straight chain olefinic, the C₃₋₁₂branched chain olefinic, the C₃₋₈ cycloalkyl, the benzyl, piperazino,morpholino, alkylamino, arylamino, acetyl, acetoxy, carboxy,carboxymethyl, alkoxy or the like are substituted, they can besubstituted with any moiety that does not destroy the NO-releasingcharacter of the compounds and which, preferably, is biologicallycompatible. Accordingly, substituents to the substituted R¹-R⁵ groupscan include hydroxy, alkoxy, acyloxy, halo or benzyl, acetyl, carboxyl,carboxyalkyl, such as carboxymethyl, carboxyethyl, carboxyalkylamido,carboxydialkylamido, carboxamido, amino, alkylamino, dialkylamino,alkylcarbonyl, arylamino, diarylamino, cyano, tolyl, xylyl, mesityl,anisyl, pyrrolidinyl, formyl, dioxane, thiol, alkylthiol, aryl,heteroaryl, such as pyran, pyrrole, furan, thiophene, thiazole,pyrazole, pyridine, or pyrimidine, phenoxy, benzyloxy, phenylcarbonyl,benzylcarbonyl, nitrophenyl trialkylsilyl, nitro, sulfonyl, nitrobenzyl,trialkylammonium, alkyl, cycloalkyl, tetrahydrofuranyl,tetrahydropyranyl, piperidinyl or morpholinyl.

[0037] The substituents R¹, R², R³, R⁴ and R⁵, in various combinations,and together with the nitrogen atom or carbon atom to which they arebonded, can form unsubstituted or substituted cyclic or unsubstituted orsubstituted heterocyclic rings. The rings that are formed are fourmember rings or layers. For example, R¹ and R² together with thenitrogen atoms to which they are bonded can form a C₂₋₈ heterocyclicring. R¹ and R⁴ together with the nitrogen atom to which R¹ is bondedand with the carbon atom to which R⁴ is bonded can form a C₃-C₈heterocyclic ring. Similarly, R² and R³ can form a C₃₋₈ heterocyclicring with the nitrogen atom to which they are bonded. The heterocyclicring can also include up to one additional heteroatom, such as oxygen,nitrogen or sulfur.

[0038] The heterocyclic rings formed by the different combinations ofR¹, R², R³, R⁴ and R⁵ can be, for example, a piperazino, a morpholino, ahexamethyleneimino, an imidazolyl, a pyrrolidino, a piperidino or thelike. Likewise, R⁴ and R⁵ together with the carbon atom to which theyare bonded can form a C₃₋₈ cycloalkyl, or a heterocyclic such astetrahydrofuranyl, dioxanyl or the like. Further, R⁴ and R⁵ togetherwith the carbon atom to which they are bonded can form a1,4-benzodioxane, 1,3-benzodioxole, tetrahydronaphthlene,octahydronaphthalene, piperazine, morpholine, tetrahydroquinoline,tetrahydroquinoxaline, or tetrahydroisoquinoline.

[0039] Each of the cyclic or heterocyclic rings formed with R¹ and R²,or R² and R³, or R¹ and R⁴, or R⁴ and R⁵ can be substituted with one ormore substituents, including, by way of example, C₃₋₈ cycloalkyl,alkoxy, benzyl, fused benzene, phenyl, an alkoxy, acetyl, carboxyl,carboxymethyl, carboxyethyl, carboxamido, amino, alkyl amino,dialkylamino, pyrrolidine, dioxane, thiol or alkylthiol, or a heteroarylsuch as pyran, pyrrole, furan, thiophene, thiazole, pyrazole, pyridine,or pyrimidine.

[0040] The compounds of the present invention can be derived fromexisting pharmaceutical agents that contain the amidine group. Forexample, a compound of Formula III preferably is one in which R¹ and R²are hydrogen and. R³ is the entire substituent attached to an amine of apharmaceutical agent such as, for example, tryptamine, serotonin,histamine, valcyclovir, adenosine, thyroxine, guanine, guanosine,ubenimex, glucosamine, mannosamine, mycosamine, sphingosine,thienamycin, penicillamine and rimantadine. Similarly, for example, thepresent invention provides a compound of Formula III, in which R¹ and R²are hydrogen and R³ is the entire substituent attached to an amine of anamino acid. The amino acid is preferably lysine, tryptophan orhydroxy-tryptophan.

[0041] The present invention also provides compounds of

[0042] wherein R¹-R⁶ can be a wide variety of substituents withoutdeparting from the scope of the present invention owing to the fact thatany compound which includes the characteristics of the chemical linkageidentified above is contemplated he-rein.

[0043] Thus, in the compounds of Formula IV and Formula V, R¹, R², R⁵and R⁶ are independently hydrogen, an is unsubstituted or substitutedC₁₋₁₂ straight chain alkyl, an unsubstituted or substituted C₃₋₁₂branched chain alkyl, an unsubstituted or substituted C₃₋₁₂ straightchain olefinic, an unsubstituted or substituted C₃₋₁₂ branched chainolefinic, a substituted or unsubstituted benzyl, a substituted orunsubstituted piperazino, a substituted or unsubstituted morpholino,amino, an unsubstituted or substituted alkylamino, an unsubstituted orsubstituted arylamino, an unsubstituted or substituted dialkylamino, anunsubstituted or substituted diarylamino, carboxyalkylamino,carboxydialkylamino, cyano, tolyl, xylyl, anisyl, mesityl, nitro, anunsubstituted or substituted acetyl, an unsubstituted or substitutedacetoxy, carboxy, an unsubstituted carboxyalkyl, such as anunsubstituted or substituted carboxymethyl, or an unsubstituted orsubstituted carboxyethyl, an unsubstituted or substituted alkylcarbonyl,thiol, an unsubstituted or substituted alkylthio, an unsubstituted orsubstituted alkoxy, carboxamido, an unsubstituted or substitutedalkylcarboxamido, or an unsubstituted or substituted dialkylcarboxamido.

[0044] In the compounds of Formula IV and V, R³ and R⁴ are independentlychosen from hydrogen, an unsubstituted or substituted C₁₋₁₂ straightchain alkyl, an unsubstituted or substituted C₃₋₁₂ branched chain alkyl,an unsubstituted or substituted C₃₋₁₂ straight chain olefinic., anunsubstituted or substituted C₃₋₁₂ branched chain olefinic, asubstituted or unsubstituted C₃₋₈ cycloalkyl, a C₃₋₈ heterocyclic ringbound through a carbon atom and in which the heteroatom is oxygen ornitrogen, a substituted or unsubstituted naphthyl, a substituted orunsubstituted tetrahydronaphthyl, a substituted or unsubstitutedoctahydronaphthyl, benzyl or substituted benzyl, substituted with up tothree substituents, or a substituted or unsubstituted phenyl,substituted with up to three substituents. Such compounds areadvantageous because they are more “organic” than polyamines, such thatsimple aromatic enamines can be made to be water-insoluble, yet releaseNO, and to be heat-stable.

[0045] When any of the groups indicated above for R¹-R⁵ are identifiedas being substituted, such as the C₁₋₁₂ straight chain alkyl, the C₃₋₁₂branched chain alkyl, the C₃₋₁₂ straight chain olefinic, the C₃₋₁₂branched chain olefinic, the C₃₋₈ cycloalkyl, the benzyl, piperazino,morpholino, alkylamino, arylamino acetyl, acetoxy carboxy, carboxymethylalkoxy or the like, they can be substituted with any moiety that doesnot destroy the NO-releasing character of the compounds and which,preferably, is biologically compatible. Accordingly, substituents to thesubstituted R¹-R⁵ groups can include hydroxy, alkoxy, acyloxy, halo orbenzyl, acetyl, carboxyl, carboxyalkyl, such as carboxymethyl,carboxyethyl, carboxyalkylamido, carboxydialkylamido, carboxamido,amino, alkyl amino, dialkylamino, alkylcarbonyl, arylamino, diarylamino,tolyl, xylyl, mesityl, anisyl, pyrrolidine, formyl, dioxane, thiol,alkylthiol, aryl, heteroaryl, such as pyran, pyrrole, furan, thiophene,thiazole, pyrazole, pyridine, or pyrimidine, phenoxy, benzyloxy,phenylcarbonyl, benzylcarbonyl, nitrophenyl trialkylsilyl, nitro.

[0046] The groups R¹-R⁶ of the compounds of Formula IV and Formula V invarious combinations, and together with the nitrogen atom or carbon atomto which they are bonded and intervening atoms, can form heterocyclicrings. For example, and not in limitation, a compound of Formula V inwhich R³ and R⁴, together with the nitrogen atom to which they arebonded, can form a C₃₋₈ heterocycle. The is heterocycle can be furthersubstituted with a heteroatom.

[0047] As another example, in the Formula V compound, R¹ and R⁶,together with the C═C—C through which they are bonded, can form asubstituted or unsubstituted C₃₋₁₂ cycloalkyl. Similarly, for a compoundof Formula IV, R² and R³, together with the nitrogen to which R³ isbonded, can form a C₃₋₈ heterocycle. The heterocycle can be furthersubstituted with a heteroatom, or an aromatic ring, which can besubstituted with a C₁₋₆ alkyl or a C₁₋₆ alkoxy. Also, R⁵ and R⁴ can forma C₃₋₈ heterocycle, which can also be substituted.

[0048] In Formulas IV and V, R³ and R⁴ together with the nitrogen atomto which they are bonded can form a C₃₋₈ heterocyclic ring or a C₃₋₈substituted heterocyclic ring or a C₃₋₈ unsubstituted or substitutedheterocyclic ring containing up to two additional heteroatoms selectedfrom the group O, S, N.

[0049] Also, R⁵ and R⁶ together with the carbon to which they are bondedcan form a substituted or unsubstituted C₄₋₈ cycloalkyl.

[0050] With respect to the compounds of Formulas I, II and III, R¹-R⁵can be selected such that they represent the substituents attached tothe amidine of nasal decongestants and α-adrenergic antagonists such astetrahydrozoline, idazoxan, phentolamine, xylometazoline and the like.

[0051] In accordance with another aspect of the invention, there isprovided a method for the preparation of the amidine- andenamine-derived NO-releasing compounds described herein. In oneembodiment, the method comprises reacting an amidine, preferably anamidine of Formula Ia, IIa or IIIa, with gaseous NO in acetonitrile or asimilar solvent to produce an N₂O₂ ⁻-containing compound. R¹ and R⁴together with the nitrogen atom to which R¹ is bonded and with thecarbon atom to which R⁴ is bonded can form a C₃-C₈ heterocyclic ring.

[0052] The solvent is preferably chosen so that the is starting amidineor enamine is soluble whereas the resulting NO₂ ⁻-containing product isinsoluble and so precipitates as it forms in order to drive the reactionto completion. Anhydrous and neutral solvents such as acetonitrile,tetrahydrofuran, dioxane and ether are preferred because they do notcause hydrolysis of the water-sensitive amidines and enamines. However,it is anticipated that low yields of the desired products can also formin partly aqueous and/or basic solvents such as NaOMe in methanol or wettetrahydrofuran among others, and such solvents may also be used.

[0053] The resulting compound in accordance with the method of theinvention contains either one or two N₂O₂ ⁻ functional groups dependingupon the structure of the amidine reactant, as, for example, shownbelow.

[0054] Methods for the preparation of the amidines, such as those ofFormulas Ia, IIa and IIIa, are well known and have been reviewed in tworeference books, Gautier et al., “Preparation and Synthetic Uses ofAmidines,” Chapter 7 in The Chemistry of Amidines and Imidates, Editor:Patai, pp. 283-348, Wiley, 1975, and Boyd, “Recent Advances in theSynthesis of Amidines,” Chapter 7 in The Chemistry of Amidines andImidates, Volume 2, Editors: Patai and Rappoport, pp. 339-3.67, Wiley,1991. These methods can be used by those skilled in the art to prepare awide variety of amidines which can then be made into NO-releasingdiazeniumdiolates in accordance with the invention.

[0055] By way of example and not in limitation, the preparation of anNO-releasing amidine-derived diazeniumdiolate can be illustrated by thereaction of 2-methyl-2-imidazoline with NO as follows:

[0056] Although the initial reaction products are the amidinium salts(either intramolecular or intermolecular), standard metathesis reactionscan be employed to change the cation to any pharmaceutically acceptableion. This is illustrated above by the reaction involving sodiummethoxide in methanol, which produces the disodium salt. Also, byvarying the synthesis procedures, the intramolecular or intermolecularsalt or a mixture thereof can be obtained; the reaction of2-methyl-2-imidazoline with NO in NaOMe/MeOH to directly form the sodiumsalt is an example of such a reaction.

[0057] While applicants do not wish to be bound to any particulartheory, the above reactions are believed to be explained by the reactionof NO with the little exploited enediamine tautomers of the amidines.The enediamine tautomers are known to exist in solution and were firstproposed to explain deuterium exchange in NMR solutions as follows(Isagulyants et al., Zh. Prikl. Khim. 41: 1585-1590 (1968); also, inChem. Abstracts 70: 11629h (1969))

[0058] Accordingly, while not being bound to any particular theory, itis believed that the reaction of the above undeuterated compound with anNO dimer is as follows:

[0059] The reaction is believed to stop at this stage due to sterichindrance and/or precipitation of the product from solution.

[0060] When either the amidinium or sodium salt of the NO-releasingdiazeniumdiolate derived from 2-methyl-2-imidazoline was dissolved inwater and acidified, a voluminous gas evolution resulted and thesolution turned blue in color and remained so for many hours after gasevolution had ceased. When the experiment was repeated at pH 7.4, theevolving gas was identified as a mixture of 2 parts NO (determined bychemiluminescence) and 1 part N₂O (determined by gas chromatography).Nitrous oxide (N₂O), being the end product of HNO dimerization anddehydration, provided a measure of HNO production via the equation(Nagasawa et al., J. Med. Chem. 33: 3122-3124 (1990)):

[0061] Again, while not wishing to be bound to any particular theory, itis believed that the partial mechanistic explanation for theseobservations is as follows:

[0062] The last step in this mechanism is not well understood but hasprecedent in the known release of NO by FK409 and closely relatedcompounds which are used as standard sources of NO (Kita et al., Eur. J.Pharmacol. 257: 123-130 (1994)). Although this mechanism is oneexplanation for the observed NO and N₂O release, it is a very incompleterepresentation of what actually happens to any given compound in aqueoussolution. Specifically, amidines are known to be subject to hydrolysisat rates that range from very slow, such as for 2-methyl-2-imidazoline(Haake et al., J. Org. Chem. 35: 4063-4067 (1970))

[0063] to very fast for acetamidine (Davies et al, Chem. Ind. (London):628 (1958))

[0064] Thus, at any intermediate stage of HNO or NO release, the amidinogroup could hydrolyze and no further gas would be generated. A compoundin which the amidine hydrolyzes rapidly would release much HNO but verylittle NO, whereas a compound in which the amidine hydrolyzes slowlywould have time for NO release, which is the last step, and would thusrelease a larger mount of NO. In this regard, compounds of Formula I (asset forth above) cannot be hydrolyzed by the above mechanism. It isbelieved that these mono-N₂O₂ ⁻ derivatives break down via two competingpathways, one of which appears to be simple reversal of the synthesisstep to release NO, while the other may be a single scission to yieldone molecule of HNO and a mono-C-nitroso compound. Since the amidinotautomers cannot come into conjugation with this nitroso group, it doesnot serve as a source of NO, and since hydrolysis of the amidinecompetes with the first pathway, compounds derived from amidines offormula I release only small amounts of NO, but over a long period oftime. In such cases, the reaction of an amidine with NO results in asterically hindered compound of formula I, which is apparently inclinedto break apart differently than previously reported, less hindered N₂O₂⁻ compounds.

[0065] In another embodiment of the present inventive method, anenamine, preferably an enamine of Formula IV or V, is reacted with NO toproduce an N₂O₂ ⁻ containing compound. Enamines are prepared from anequimolar mixture of an aldehyde or ketone and a secondary amine viadehydration as follows.

[0066] Methods for preparing enamines and lengthy discussions of theirproperties are readily available to synthetic chemists (see, e.g.,Hickmott, Tetrahedron 38: 1975-2050 (1982); Hickmott, Tetrahedron 38:3363-3446 (1982); Cook, Enamines: Synthesis. Structure and Reactions,Marcel Dekker, New York (1988); and Szmuszkovicz, Enamines, Vol. 4 ofAdv. in Org. Chem. Methods and Results, Wiley Interscience, New York(1963)). Although literally thousands of carbonyl compounds are used inthis reaction, the amines are usually limited to a select few, such asdimethylamine, diethylamine, piperidine, pyrrolidine, morpholine, andN-methylaniline.

[0067] Unlike the amidine-derived compounds, the enamine-deriveddiazeniumdiolates do not appear to release any NO⁻ or N₂O. Rather, theyrelease small amounts of NO over prolonged periods of time (e.g., 1 weekin phosphate-buffered saline). As with amidine-derived compounds, themechanism of NO release is complicated by a competing hydrolysismechanism as set forth below.

[0068] It will be appreciated by those of ordinary skill in the art thateither the amidine-derived or enamine-derived diazeniumdiolates inaccordance with the present invention can be formed as a salt, andpreferably, a biologically acceptable salt. Accordingly, the counterionis preferably any biologically acceptable acceptable counterion. Suchcounterions can include, but are not limited to, sodium ion, potassiumion, quaternary ammonium ions, and the like.

[0069] Also provided by the present invention is a method of producing anitric oxide-releasing compound from a compound containing a primaryamine and/or a secondary amine. The method comprises (a) treating thecompound containing a primary amine and/or a secondary amine with anacetamidating agent, by which is meant an organic chemical reagentcapable of transferring the CH₃C (═NH)⁻ group from itself to anothermolecule. Such reagents are generally acetimidates, for example, ethylacetimidate, or thioimidates, for example, benzyl thioacetimidate. Thepreferred reagent for use in the context of this method is thatdescribed in Shearer et al., Tetrahedron Letters 38(2): 179-182 (1997),so as to form an acetamidine derivative of the compound containing theprimary amine and/or secondary amine, and (b) treating the acetamidinederivative with nitric oxide gas to form an amidine-deriveddiazeniumdiolate. This method in accordance with the invention providesa method for preparing an amidine-based diazeniumdiolate in which theNO-releasing N₂O₂ ⁻ functional group is bound to a carbon atom ratherthan to the original primary or secondary amine. In this way, manyprimary and secondary amine-containing drugs can be subjected to theacetamidating reagent to produce the amidine which can then be convertedto the diazeniumdiolate. This is advantageous particularly in the caseof primary amines where the N—N₂O₂ ⁻ functionality is not very stable.

[0070] As is well known in the art, nitric oxide and compoundscomprising N₂O₂ ⁻ functional groups can have a wide range of utilities,in part because of the multifaceted role of nitric oxide inbioregulatory processes. Accordingly, the present invention alsoprovides a composition, including a pharmaceutical composition,comprising a present inventive diazeniumdiolate. Preferably, thepharmaceutical composition additionally comprises a pharmaceuticallyacceptable carrier.

[0071] One skilled in the art will appreciate that suitable methods ofadministering a diazeniumdiolate composition of the present invention toan animal, such as a mammal, are available, and, although more than oneroute can be used to administer a particular composition, a particularroute can provide a more immediate and more effective reaction thananother route. Pharmaceutically acceptable carriers are also well-knownto those who are skilled in the art. The choice of carrier will bedetermined, in part, both by the particular composition and by theparticular method used to administer the composition. Accordingly, thereis a wide variety of suitable formulations of the pharmaceuticalcompositions of the present invention.

[0072] Formulations suitable for oral administration can consist of. (a)liquid solutions, such as an effective amount of the diazeniumdiolatedissolved in diluents, such as water or saline, (b) capsules, sachets ortablets, each containing a predetermined amount of the activeingredient, as solids br granules, (c) suspensions in an appropriateliquid, and (d) suitable emulsions.

[0073] Solutions may also be formulated using known preservatives foramidine-based nasal decongestants.

[0074] Tablet forms can include one or more of lactose, mannitol, cornstarch, potato starch, microcrystalline cellulose, acacia, gelatin,colloidal silicon dioxide, droscarmellose sodium, talc, magnesiumstearate, stearic acid, and other excipients, colorants, diluents,buffering agents, moistening agents, preservatives, flavoring agents,and pharmacologically compatible is carriers. Lozenge forms can comprisethe active ingredient in a flavor, usually sucrose and acacia ortragacanth, as well as pastilles comprising the active ingredient in aninert base, such as gelatin and glycerin or sucrose and acaciaemulsions, gels, and the like containing, in addition to the activeingredient, such carriers as are known in the art.

[0075] The diazeniumdiolates of the present invention, alone or incombination with other suitable components, can be made into aerosolformulations to be administered via inhalation. These aerosolformulations can be placed into pressurized acceptable propellants, suchas dichlorodifluoromethane, propane, nitrogen, and the like.

[0076] Formulations suitable for parenteral administration includeaqueous and non-aqueous solutions, isotonic sterile injection solutions,which can contain anti-oxidants, buffers, bacteriostats, and solutesthat render the formulation isotonic with the blood of the intendedrecipient, and aqueous and non-aqueous sterile suspensions that caninclude suspending agents, solubilizers, thickening agents, stabilizers,and preservatives. The formulations can be presented in unit-dose ormulti-dose sealed containers, such as ampules and vials, and can bestored in a freeze-dried (lyophilized) condition requiring only theaddition of the sterile liquid carrier, for example, water, forinjections, immediately prior to use. Extemporaneous injection solutionsand suspensions can be prepared from sterile powders, granules, andtablets of the kind previously described.

[0077] The dose administered to an animal, particularly a human, in thecontext of the present invention should be sufficient to effect atherapeutic response in the animal over a reasonable time frame. Thedose will be determined by the strength of the particular compositionsemployed (taking into consideration, at least, the rate of NO evolution,the extent of NO evolution, and the bioactivity of any decompositionproducts derived, from the diazeniumdiolates) and the condition of theanimal, as well as the body weight of the animal to be treated. The sizeof the dose also will be determined by the existence, nature, and extentof any adverse side-effects that might accompany the administration of aparticulars-composition. A suitable dosage for internal administrationis 0.01 to 100 mg/kg per day. A preferred dosage is 0.01 to 35-mg/kg perday. A more preferred dosage is 0.05 to 5 mg/kg per day. A suitableconcentration of a enamine- or amidine-derived diazeniumdiolate inpharmaceutical compositions for topical administration is 0.05 to 15%(by weight). A preferred concentration is from 0.02 to 5%. A morepreferred concentration is from 0.1 to 3%.

[0078] In view of the above, the present invention provides methods ofusing a nitric oxide-releasing amidine- or enamine-deriveddiazeniumdiolate. In one embodiment, a method of treating an animal,such as a mammal, with a biological disorder treatable with nitricoxide, is provided. The method comprises administering to the animal,e.g., the mammal, in need thereof an amount of an enamine- oramidine-derived diazeniumdiolate sufficient to treat the biologicaldisorder in the animal. In this embodiment, “biological disorder” can beany biological disorder, including hypertension, restenosis, impotency,and a biological disorder due to a genetic defect or infection with aninfectious agent, such as a virus, bacterium or parasite, as long as thedisorder is treatable with nitric oxide.

[0079] With regard to the above, NO- and/or NO⁻-releasing compoundsderived from amidines are advantageous inasmuch as amidines are presentin many already approved medicinal agents, e.g., tranquilizers,α-adrenergic antagonists, like phentolamine, and nasal decongestants.Specific examples include tolazoline and diazoxide. Other examples ofamidine-containing compounds include methyl pyrimidine and 1,8-diaminooctahydronaphthalene.

[0080] In another embodiment of a method of use, a method is providedfor treating an animal, such as a mammal, for infection with, forexample, a virus, a bacterium, or a parasite. The method comprisesadministering to the animal, e.g., the mammal, an amount of adiazeniumdiolate sufficient to treat the infection in the animal.

[0081] In yet another embodiment, a method for treating an animal, suchas a mammal, for cancer is provided. The method comprises administeringto the animal, e.g., the mammal, an amount of diazeniumdiolatesufficient to prevent the growth or metastasis of the cancer in theanimal or to render it more susceptible to radiation or chemotherapy.

[0082] In another embodiment, a method is provided for treating aninanimate object for the presence of a potentially infectious virus,bacterium, or parasite. The method comprises contacting the inanimateobject with an amount of a present inventive diazeniumdiolate sufficientto reduce the presence of the potentially infectious virus, bacterium orparasite. By “potentially infectious” is meant the capability ofinfecting an animal, such as a mammal.

[0083] It is contemplated that the diazeniumdiolates derived fromenamines and amidines in accordance with the present invention can beused to coat prostheses, stents, and medical implants, such as breastimplants, prior to surgical introduction into the body as a means ofreducing the risk of solid state carcinogenesis associated therewith, oras a means of preventing adhesion of platelets to the implants.Additionally, the prostheses and implants can be manufactured using anenamine- or amidine-derived diazeniumdiolate as an integral component ofthe starting materials. Medical devices incorporating an enamine- oramidine-derived diazeniumdiolate provide an invaluable two-prongedapproach to the treatment of many biological disorders, providing usefulmedical structures that also advantageously provide local release of NO.

[0084] The diazeniumdiolates derived from enamines and amidines alsohave utility in the in vitro study of NO biology.

EXAMPLES

[0085] The following examples further illustrate the present inventionand, of course, should not be construed as in any way limiting itsscope.

[0086] All melting points were determined on a hot stage and areuncorrected. The ¹H NMR spectra were determined at 200 MHz with a VarianXL-200 spectrometer and the ¹³C NMR spectra were obtained at 50 MHzusing the same instrument. The chemical shifts are expressed in δ values(ppm) relative to either tetramethylsilane or sodium3-(trimethylsilyl)propionate-d₄ as internal standards. Elementalanalyses were performed by Atlantic Microlabs, Inc. (Norcross, Ga.).

[0087] Except as noted here, all reagents and amines were obtained fromAldrich Chemical Company (Milwaukee, Wis.). Reaction solvents wereAldrich anhydrous grade but all others were reagent grade. Commercialgrade nitric oxide was obtained from Matheson Gas Products and was usedas received.

[0088] Reactions under pressure were conducted in standard glasshydrogenation bottles as previously described (Hrabie et al., J. Org.Chem. 58: 1472-1476 (1993)). The general directions are repeated herefor completeness.

[0089] Given that stainless steel (SS) is required for prolongedexposure to NO gas and amines degrade most types of stoppers andgaskets, a specialized reactor modeled after the standard Parr 3911hydrogenation apparatus (Parr Instrument Co., Moline, Ill.) wasconstructed. The reservoir was replaced by a type 304 SS gas samplingcylinder equipped with SS fittings is (available from-any “valve andfitting” plumbing supply company). The valves were diaphragm-sealpackless type (Aldrich), and the pressure gauges were SS (Air Products).The usual Parr clamp and bottle system was employed but was connected tothe gas reservoir via a Teflon tube and mounted to allow stirring with amagnetic stirrer.

[0090] All of the analytical data given were obtained using the productsas isolated directly from the reaction mixtures.

Example 1

[0091] This example describes a generalized procedure for thepreparation of NO- and/or NO⁻-releasing compounds from amidines.

[0092] A solution of the appropriate amidine, which was obtainedcommercially (Aldrich) or synthesized in accordance with standardprocedures, in the desired solvent was placed in a standard Parrhydrogenation bottle. Nitrogen was passed through the apparatus andbubbled through the solution for 5-10 min, the bottle was clamped, andNO gas was admitted to a pressure of 5 atm. The solution was stirred forthe indicated time at room temperature with addition of NO as neededduring the first 5-6 h to maintain the reservoir pressure. Excess NO wasthen vented and N₂ was bubbled through the resultant white slurry for 5min. The product was isolated by filtration, washed with the reactionsolvent, then washed with ether and dried in vacuo for several hours.All of the products were amorphous, voluminous white powders, which wereair-stable but were stored in a refrigerator.

Example 2

[0093] This example describes the preparation of 2-methyl-2-imidazolinetetrakis(nitric oxide)adduct and its sodium salt.

[0094] A solution of 2-methyl-2-imidazoline (lysidine, 5.0 g, 59.4 mmol)in 150 ml acetonitrile was reacted with NO for 28 h as described above.Yield 3.59 g (49%); m.p. 102-103° C. dec.; ¹H NMR (D₂O) δ 1.92 (6H, s),3.51 (8H, s), 3.67 (4H, s); ¹³C NMR (D₂O) 24.8, 42.4, 42.5, 44.6, 51.3,51.7, 163.5, 177.2; UV (0.01 N NaOH) λ_(max) 260 nm,=13,600 M⁻¹cm⁻¹, 206nm, ε=22,500. Anal. Calcd for C₁₂H₂₄N₁₀O₄: C, 38.71; H, 6.50; N, 37.61.Found: C, 38.92; H, 6.55; N, 37.62.

[0095] To prepare the disodium salt, 1.74 g of a 25% NaOMe in MeOHsolution (Aldrich, 8.06 mmol) was diluted with 0.5 ml MeOH and to thiswas added 1.5 g of the above diimidazolinium salt (8.06 mmol). The solidslowly dissolved and then re-precipitated. The slurry was diluted withacetonitrile, filtered and the solid dried in vacuo to afford a whitepowder. Yield 0.92 g (92%). m.p. >180° C. (chars); ¹H NMR (D₂O) δ2.7-2.8 (2H, m), 3.3-3.4 (2H, m).

Example 3

[0096] This example describes the preparation of acetamidine tetrakis(nitric oxide) adduct.

[0097] A solution of acetamidine hydrochloride (7.0 g, 74.0 mmol) in 150ml acetonitrile was treated with 16.93 ml of 25% NaOMe in MeOH (74.0mmol) and the precipitated sodium chloride was removed by filtration.The resulting solution was treated with NO for 16 h to yield a tanpowder. Yield 5.95 g (82%) m.p. >150° C. (chars); ¹H NMR (D₂O) δ 2.21(s); ¹³C NMR (D₂O) 20.8, 51.8, 57.7, 164.6.

Example 4

[0098] This example describes the preparation of 2-iminopiperidinebis(nitric oxide)adduct.

[0099] A solution of 2-iminopiperidine hydrochloride (5.0 g, 37.2 mmol)in 200 ml acetonitrile was treated with 8.5 ml of 25% NaOMe in MeOH(37.2 mmol) and 10 ml MeOH and the precipitated sodium chloride wasremoved by filtration. The resulting solution was treated with NO for 23h to yield an off-white powder. Yield 4.5 g (95%); m.p. 110-112° C.(dec.); ¹H NMR (D₂O) δ 1.8-1.9 (6H, —m), 2.55-2.65 (2H, m), 2.85-2.95(2H, m), 3.3-3.4 (2H, m), 3.5-3.6 (2H, m); ¹³C NMR (D₂O) 19.0, 20.3,23.0, 28.3, 29.0, 43.7, 44.1, 90.6, 100.5, 162.6.

Example 5

[0100] This example describes the preparation of2-cyclohexyl-2-imidazoline bis (nitric oxide) adduct.

[0101] The starting material for this preparation was produced by themethod described by Neef et al. (J. Org. Chem. 46: 2824-2826 (1981)). Asolution of 2-cyclohexyl-2-imidazoline (5.0 g, 32.8 mmol) in 300 mlacetonitrile was reacted with NO for 78 h. Yield 6.66 g (97%); m.p.158-159° C. (dec.); ¹H NMR (D₂O) δ 1.4-1.7 (6H, m), 1.9-2.1 (2H, m),2.5-2.6 (2H, m), 4.0 (4H, S); ¹³C NMR (D₂O) 23.9 (2C), 26.6, 34.3 (2C),47.3.(2C), 73.0, 173.4.

Example 6

[0102] This example describes the preparation of tetrahydrozoline bis(nitric oxide) adduct.

[0103] A solution of tetrahydrozoline hydrochloride (10.0 g, 42.25 mmol)in 9.66 ml of 25% NaOMe in MeOH (42.25 mmol NaOMe) was diluted with 200ml acetonitrile and the precipitated sodium chloride was removed byfiltration. The resulting solution was treated with NO for 24 h. Yield9.0 g (82%); m.p. 168-169° C. (dec.); ¹H NMR (D₂O) δ 1.8-1.9 (2H, m),2.3-2.45 (1H, m), 2.9-3.0 (3H, m), 4.00 (4H, s), 7.15-7.47 (4H, m); ¹³CNMR (D₂O) 20.4, 30.6, 34.7, 47.7 (2C), 76.0, 129.7, 13.0.7, 131.8,133.0, 133.1, 141.5, 173.7. Anal. Calcd. for C₁₃H₁₆N₄O₂: C, 59.99; H,6.20; N, 21.52. Found: C, 60.05; H, 6.14; N, 21.48.

Example 7

[0104] This example describes the preparation of idazoxanbis (nitricoxide) adduct available from Research Biochemicals, Inc. (Natick, HA).

[0105] A solution of idazoxan hydrochloride (1.00 g, 4.155 mmol) in amixture of 0.95 ml 25% NaOMe in MeOH (4.155 mmol NaOMe) and 3 ml MeOHwas diluted with 40 ml acetonitrile and the precipitated sodium chloridewas removed by filtration. The resulting solution was treated with NOfor 21 h. Yield 0.62 g (56%); m.p. 152-154° C. (dec.); ¹H NMR (D₂O) δ4.04 (4H, s), 4.64 (1H, d), 5.13 (1H, d), 7.02-7.22 (4H, m). Anal.Calcd. for C₁₃H₁₆N₄O₂: C, 49.81; H, 4.94; N, 21.12. Found: C, 50.22; H,4.61; N, 20.98.

Example 8

[0106] This example describes a general procedure for preparation ofdiazeniumdiolate derivatives of enamines.

[0107] Enamines were prepared from an equimolar mixture of an aldehydeand ketone and a wide variety of secondary amines via dehydration. Suchmethods are described in Hicknott, Tetrahedron 38: 1975-2050, and3363-3446 (0.1982); Cook, Enamines: Synthesis, Structure and Reactions,Marcel Dekker, New York (1988); and Szmuszkovicz, “Enamines”, Chapter 4,In advances in Org. Chem, Methods and Results, Wiley Interscience, NewYork (1963). Preferred amines include dimethylamine, diethylamine,piperidine, pyrrolidine, morpholine and N-methyl-aniline.

[0108] These compounds were prepared according to the general procedureset forth in Example 1, except that the reactions were cooled whenrequired and some gave crystalline products as indicated in theindividual descriptions.

Example 9

[0109] This example describes the preparation of cyclohexanonemorpholine enamine bis(nitric oxide) adduct.

[0110] A solution of the enamine derived from morpholine andcyclohexanone (15.0 g, 89.7 mmole) in 150 ml ethyl ether was cooled indry ice without stirring and reacted with NO for 20 h as it warmed toroom temperature. Workup as above produced large clear crystals ofproduct. Yield 8.14 g (40%); m.p. 85-87° C.; ¹H NMR (CD₃CN) δ 1.5-2.3(6H, m), 2.44-2.55 (4H, m), 2.85-2.96 (4H, m), 5.13-5.18 (1H,m),5.23-5.27 (1H, t), 11.6 (1H, br.s); ¹³C NMR (CD₃CN) 19.2, 24.7, 28.6,50.6 (2C), 67.1, 67.5 (2C), 112.5, 141.3; exact mass calcd. forC₁₀H₁₇N₃O₃ (M⁺) 227.1269, found 227.1254. Anal. Calcd. for C₁₀H₁₇N₃O₃:C, 52.85; H, 7.54; N, 18.49. Found: C, 53.32; H, 7.63; N, 18.76.

Example 10

[0111] This example describes the preparation of isobutyraldehydemorpholine enamine bis. (nitric oxide) adduct.

[0112] A solution of the enamine derived from morpholine andisobutyraldehyde (7:0 g, 49.6 mmole) in 100 ml THF was reacted with NOfor 22 h as described above. Yield 4.05 g (41%); m.p. 91-92° C.; ¹H NMR(D₂O) δ 1.48 (6H, s), 3.25-3.31 (4H, m), 3.92-3.98 (4H, m), 5.26 (1H,S); ¹³C NMR (D₂O) 23.2 (2C), 46.1 (2C), 66.6 (2C), 75.7, 95.2; exactmass calcd. for C₈H₁₆N₃O₃ (MH⁺) 202.1192; found 202.1137. Anal. Calcd.for C₈H₁₅N₃O₃: C, 47.75; H, 7.51; N, 20.88. Found: C, 47.74; H, 7.70; N,20.13.

Example 11

[0113] This example describes the preparation ofcyclohexanecarboxaldehyde morpholine enamine bis (nitric oxide) adduct.

[0114] A solution of 4-(cyclohexylidenemethyl)morpholine (10.0 g, 55.2mmol) in 20mL of CH₃CN was cooled at 0° C. in an ice bath and reactedwithout tirring with NO as described above for 6 h and then warmed toroom temperature. The product was isolated by filtration, washed withCH₃CN, then ether and dried in vacuo. Yield 7.13 g (54%); mp 115-117°C.; ¹H NMR δ 1.25-1.40 (2H, m), 1.48-1.70 (4H, m), 1.95-2.40 (4H, m),3.20-3.26 (4H, m), 3.90-3.96 (4H, m), 5.05 (1H, s); ¹³C NMR δ 24.1 (2C),27.8, 31.3 (2C), 46.3 (2C), 67.1 (2C), 78.0, 95.7.

[0115] Anal. Calcd for C₁₁H₁₉N₃O₂: C, 54.76; H, 7.94; N, 17.41. Found:C, 54.93; H, 8.04; N, 17.60.

Example 12

[0116] This example describes the preparation of isobutyraldehydepiperidine enamine bis(nitric oxide) adduct (25).

[0117] A solution of the enamine derived from piperidine andisobutyraldehyde (5.0 g, 35.9 mmole) in 150 ml CH₃CN was stirred at roomtemperature and reacted with NO for 23 h as described above. Yield 3.25g (45%); m.p. 84-85° C.; ¹H NMR (D₂O) δ 1.48 (6H, s), 1.66-1.83 (6H, m),3.13-3.18 (4H, m), 5.25 (1H, s). ¹³C NMR (D₂O) 23.2 (2C), 24.3, 25.1(2C), 47.4 (2C), 7S.5, 95.2. Anal. Calcd. for C₉H₁₇N₃O₂: C, 54.25; H,8.60; N, 21.09. Found: C, 52.69; H, 8.56; N, 21.28.

Example 13

[0118] This example describes the preparation of isobutyraldehydepyrrolidine enamine bis (nitric oxide) adduct.

[0119] A solution of N-(2-methyl-1-propenyl)pyrrolidine (10.0 g, 79.9mmol) in 200 mL of CH₃CN was cooled to 0° C. in an ice bath and reactedwithout stirring with NO as described above for 6 h and then warmed toroom temperature. The product was isolated by filtration, washed withCH₃CN, then ether and dried in vacuo. Yield 88.8 g (60%); mp 75-76° C.;¹H NMR δ 1.48 (6H, s), 1.98-2.03 (4H, m), 3.23-3.32 (4H, m), 5.25 (1H,S); ¹³C NMR 23.2 (2C), 26.5 (2C), 48.3 (2C), 75.6, 95.2.

Example 14

[0120] This example describes the preparation of isobutyraldehydeN-methylaniline enamine bis (nitric oxide) adduct.

[0121] A solution of the enamine derived from N-methylaniline andisobutyraldehyde (5.0 g, 31.0 mmole) in 150 ml CH₃CN was stirred at roomtemperature and reacted with No for 20 h. The resulting pale yellowsolution was concentrated to dryness on a rotary evaporator and theresidual solid was recrystallized from absolute ethanol to yield 2.26 g(33!k) of product as pale, cream-colored needles. m.p. 83-84° C.; ¹H NMR(CDCl₃) δ 1.59 (3H, s), 1.63 (3H, s), 2.75 (3H, s), 6.00 (1H, s),6.96-7.37 (5H, m); 13C NMR (CDCl₃) 17.4, 26.8, 34.4, 75.6, 101.1, 118.9(2C), 122.7, 129.4 (2C), 149.3. Anal. Calcd. for C₁₁H₁₅N₃O₂: C, 59.71;H, 6.83; N, 18.99. Found: C, 59.77; H, 6.84; N, 19.01.

Example 15

[0122] This example describes the preparation of isobutyraldehydeN-methyl-p-toluidine enamine bis(nitric oxide) adduct.

[0123] A solution of the enamine derived from N-methyl-p-toluidine andisobutyraldehyde (5.0 g, 28.5 mmole) in 150 ml CH₃CN was stirred at roomtemperature and reacted with NO for 20 h. The resulting paleyellow-orange solution was concentrated to dryness on a rotaryevaporator and the residual off-white solid was recrystallized fromabsolute ethanol to yield 2.21 g (33%) of product as white cotton-likeneedles. m.p. 127-128° C.; ¹H NMR (CDCl₃) δ 1.58 (3H, s), 1.61 (3H, s),2.31 (3H, s), 2.71 (3H, s), 5.92 (1H, s), 6.90-7.15 (4H, m); ¹³C NMR(CDCl₃) 17.3, 20.5, 26.8, 34.9, 75.4, 101.9, 119.7 (2C), 129.9 (2C),132.7, 147.2. Anal. Calcd. for C₁₂H₁₇N₃O₂: C, 61.26; H, 7.28; N, 17.86.Found: C, 61.32; H, 7.35; N, 17.88.

Example 16

[0124] This example describes the preparation of isobutyraldehydeN-methyl-p-anisidine enamine bis (nitric oxide) adduct.

[0125] A solution of the enamine derived from N-methyl-p-anisidine andisobutyraldehyde (5.0 g, 26.1 mmole) in 150 ml CH₃CN was stirred at roomtemperature and reacted with NO for 23 h. The resulting pale brownsolution was concentrated to dryness on a rotary evaporator and theresidual oil was crystallized from absolute ethanol to yield 4.89 g(75%) of product as colorless chunky crystals. m.p. 97-98° C.; ¹H NMR(CDCl₃) δ 1.58 (3H, s), 1.60 (3H, s), 2.67 (3H, s), 3.79 (3H, s), 5.80(1H, s), 6.84-7.06 (4H, m); ¹³C NMR (CDCl₃) 17.2, 26.8, 36.1, 55.5,75.2, 103.0, 114.6 (2C), 122.8 (2C), 143.4, 156.3. Anal. Calcd. forC₁₂H₁₇N₃O₃: C, 57.35; H, 6.82; N, 16.72. Found: C, 57.36; H, 6.87; N,16.75.

Example 17

[0126] This example describes the measurement of the production of NOand N₂O by amidine/nitric oxide adducts.

[0127] As a demonstration of the efficacy of the amidine/nitric oxideadducts described herein as nitric oxide and nitroxyl releasing agents,selected compounds were dissolved in either 0.1 N HCl or pH 7.4 bufferand the headspace was monitored by chemiluminescence (to detect NO) andgas chromatography (to detect N₂O, the dehydrated dimer of HNO). Theresults are shown in Table I. TABLE I Cmpd of Ratio Yield (in moles permole cmpd) Ex. No. Solution N₂O:NO N₂O NO 2 0.1 N HCl 2:1 0.9 0.45 3 pH7.4 13:1  0.64 0.05 4 pH 7.4 6:1 0.45 0.08 5 0.1 N HCl — 0.2 N.D.* 6 pH7.4 — 0.4 N.D.*

Example 18

[0128] This example describes the measurement of the time course of NOproduction by amidine and enamine nitric oxide adducts.

[0129] To demonstrate the utility of these compounds as long-term nitricoxide releasing agents, selected compounds were dissolved in phosphatebuffer at pH 7.4 and incubated in a 37° C. thermostated water bath. TheNO release rate was measured periodically by flushing the solution withinert N₂ gas and then sweeping newly generated NO into achemiluminescence detector and integrating the signal produced over thenext 4-7 mins. NO release was measured over a period of two weeks.

[0130] None of these compounds released nitric oxide via a singlepathway which produced a release profile consistent with first orderkinetics. Accordingly, the results of each test are summarized here bygiving the initial NO release rate, the rate at one intermediatetimepoint and the total time of observed NO release for representativeexamples.

[0131] Thus, the compound of Example V (tetrahydrozolinediazeniumdiolate) showed an initial NO release rate of 3.64×10⁻¹¹ molesNO per minute per milligram of dissolved sample which decreased to2.06×10⁻¹¹ moles NO per min. per mg. after 7 days and continued forseveral weeks although the last quantitative measurement showed an NOrelease rate of 9.00×10⁻¹² moles NO per min. per mg. 15 days after thebeginning of the experiment.

[0132] Likewise, the compound of Example VI (idazoxan diazeniumdiolate)showed an initial NO release rate of 5.25×10⁻¹¹ moles NO/min./mg. whichgradually increased to 1.41×10⁻¹⁰ moles NO/min./mg. after 4 days andthen gradually decreased, reaching zero (i.e., no more NO was beinggiven off) by day 16.

[0133] Among the enamine-derived compounds, the compound of Example VII(the diazeniumdiolate of the morpholine enamine of cyclohexanone) showedan initial NO release rate of 4.2×10⁻¹¹ mole NO/min./mg. which decreasedwith nearly first order kinetics to 1.8×10⁻¹¹ mole NO/min./mg. after 3days and reached zero by day 7.

[0134] The enamine-derived diazeniumdiolate of Example VIII (from themorpholine enamine of isobutyraldehyde) showed an initial NO releaserate of 3.7×10⁻¹¹ mole NO/min./mg. which rapidly decreased to a rate of7.0×10⁻¹² mole NO/min./mg. and then remained at about this level for 4days before slowly declining, reaching zero after 7 days.

[0135] All publications cited herein are hereby incorporated byreference to the same extent as if each publication were individuallyand, specifically indicated to be incorporated by reference and were setforth in its entirety herein.

[0136] While this invention has been described with emphasis uponpreferred embodiments, it will be obvious to those of ordinary skill inthe art that the preferred embodiments may be varied. It is intendedthat the invention may be practiced otherwise than as specificallydescribed herein. Accordingly, this invention includes all modificationsencompassed within the spirit and scope of the appended claims.

What is claimed is:
 1. A compound having the chemical structural linkageas follows:

wherein C²˜C³ means either C²-C³ or C²═C³ m is 1 or 2 q is 0 or 1 p is 0or 1 provided that (1) C² is tetravalent, and bound to two or more ofC¹, C³, N¹ and N²; (2) when p=1, then q=O and C²˜C³ means C²-C³; or (3)when p=0, and q=1, then C²˜C³ means either (i) C²═C³ or (ii) C²-C³ whereC²˜N¹ means C²═N; (4) when C²˜C³ means C²-C³ and q=1 and p=0; whereinC²N¹ and C²N² means


2. A compound selected from the group consisting of:

wherein R¹-R³ are independently hydrogen, an unsubstituted orsubstituted C₁₋₁₂ straight chain alkyl, an unsubstituted or substitutedC₃₋₁₂ branched chain alkyl, an unsubstituted or substituted C₃₋₁₂straight chain olefinic, an unsubstituted or substituted C₃₋₁₂ branchedchain olefinic, a substituted or unsubstituted C₃₋₈ cycloalkyl, a C₃₋₈heterocyclic ring bound through a carbon atom and in which theheteroatom is oxygen or nitrogen, a substituted or unsubstitutednaphthyl, a substituted or unsubstituted tetrahydronaphthyl, asubstituted or unsubstituted octahydronaphthyl, benzyl or substitutedbenzyl, substituted with up to three substituents, or phenyl orsubstituted phenyl, substituted with up to three substituents; R⁴ and R⁵are independently chosen from hydrogen, an unsubstituted or substitutedC₁₋₁₂ straight chain alkyl, an unsubstituted or substituted C₃₋₁₂branched chain alkyl, an unsubstituted or substituted C₃₋₁₂ straightchain olefinic, an unsubstituted or substituted C₃₋₁₂ branched chainolefinic, a substituted or unsubstituted benzyl, an unsubstituted orsubstituted phenyl, a substituted or unsubstituted piperazino, asubstituted or unsubstituted morpholino, amino, an unsubstituted orsubstituted alkylamino, an unsubstituted or substituted arylamino, anunsubstituted or substituted dialkylamino, an unsubstituted orsubstituted diarylamino, carboxyalkylamino, carboxydialkylamino,unsubstituted or substituted tolyl, xylyl, anisyl, mesityl, anunsubstituted or substituted acetyl, an unsubstituted or substitutedacetoxy, carboxy, an unsubstituted or substituted carboxymethyl, anunsubstituted or substituted carboxyethyl, an unsubstituted orsubstituted alkylcarbonyl, thiol, an unsubstituted or substitutedalkylthio, an unsubstituted or substituted alkoxy, carboxamido, anunsubstituted or substituted alkylcarboxamido, or an unsubstituted orsubstituted dialkylcarboxamido, an unsubstituted or substituted phenoxy,an unsubstituted or substituted benzyloxy, phenylcarbonyl,benzylcarbonyl, an unsubstituted or substituted nitrophenyl,trialkylsilyl or nitro; and R¹ and R² together with the nitrogen atomsto which they are bonded form a substituted or unsubstituted C₂₋₈heterocyclic ring, or R² and R³ together with the nitrogen atom to whichthey are bonded form a substituted or unsubstituted C₃₋₈ heterocyclicring, or R¹ and R⁴ together with the nitrogen atom to which R¹ is bondedand with the carbon atom to which R⁴ is bonded and with the interveningcarbon atom form a substituted or unsubstituted C₂₋₆ heterocyclic ring,or R⁴ and R⁵ together with the carbon atom to which they are bonded forman unsubstituted or substituted C₃₋₈ cycloalkyl, or a C₄₋₈ heterocyclicring in which the heteroatom is selected from the group consisting ofoxygen, nitrogen, and sulfur, or R⁴ and R⁵ together with the carbon atomto which they are bonded form an unsubstituted or substituted1,4-benzodioxane, 1,3-benzodioxole, tetrahydronaphthlene,octahydronaphthalene, piperazine, morpholine, tetrahydroquinoline,tetrahydroquinoxaline, tetrahydroisoquinoline; with the proviso that theheterocyclic ring formed by R¹ and R², R² and R³, R¹ and R⁴, or R⁴ andR⁵ is not a five-membered heterocyclic ring in which the heteroatom isoxygen, nitrogen, or sulfur, or six-membered heterocyclic ring in whichthe heteroatom is nitrogen.
 3. The compound of claim 2 of

wherein R¹-R³ are independently hydrogen, an unsubstituted orsubstituted C₁₋₁₂ straight chain alkyl, an unsubstituted or substitutedC₃₋₁₂ branched chain alkyl, an unsubstituted or substituted C₃₋₁₂straight chain olefinic, an unsubstituted or substituted C₃₋₂ branchedchain olefinic, a substituted or unsubstituted C₃₋₈ cycloalkyl, a C₃₋₈heterocyclic ring bound through a carbon atom and in which theheteroatom is oxygen or nitrogen, a substituted or unsubstitutednaphthyl, a substituted or unsubstituted tetrahydronaphthyl, asubstituted or unsubstituted octahydronaphthyl, benzyl or substitutedbenzyl, substituted with up to three substituents, or phenyl orsubstituted phenyl, substituted with up to three substituents; R⁴ and R⁵are independently chosen from hydrogen, an unsubstituted or substitutedC₁₋₁₂ straight chain alkyl, an unsubstituted or substituted C₃₋₁₂branched chain alkyl, an unsubstituted or substituted C₃₋₁₂ straightchain olefinic, an unsubstituted or substituted C₃₋₁₂ branched chainolefinic, a substituted or unsubstituted benzyl, an unsubstituted orsubstituted phenyl, a substituted or unsubstituted piperazino, asubstituted or unsubstituted morpholino, amino, an unsubstituted orsubstituted alkylamino, an unsubstituted or substituted arylamino, anunsubstituted or substituted dialkylamino, an unsubstituted orsubstituted diarylamino, carboxyalkylamino, carboxydialkylamino,unsubstituted or substituted tolyl, xylyl, anisyl, mesityl, anunsubstituted or substituted acetyl, an unsubstituted or substitutedacetoxy, carboxy, an unsubstituted or substituted carboxymethyl, anunsubstituted or substituted carboxyethyl, an unsubstituted orsubstituted alkylcarbonyl, thiol, an unsubstituted or substitutedalkylthio, an unsubstituted or substituted alkoxy, carboxamido, anunsubstituted or substituted alkylcarboxamido, or an unsubstituted orsubstituted dialkylcarboxamido, an unsubstituted or substituted phenoxy,an unsubstituted or substituted benzyloxy, phenylcarbonyl,benzylcarbonyl, an unsubstituted or substituted nitrophenyl,trialkylsilyl or nitro; and R¹ and R² together with the nitrogen atomsto which they are bonded form a substituted or unsubstituted C₂₋₈heterocyclic ring, or R² and R³ together with the nitrogen atom to whichthey are bonded form a substituted or unsubstituted C₃₋₈ heterocyclicring, a substituted or unsubstituted C₃₋₈ heterocyclic ring, or R¹ andR⁴ together with the nitrogen atom to which R¹ is bonded and with thecarbon atom to which R⁴ is bonded and with the intervening carbon atomform a substituted or unsubstituted C₂₋₆ heterocyclic ring, or R⁴ and R⁵together with the carbon atom to which they are bonded form anunsubstituted or substituted C₃₋₈ cycloalkyl, or a C₄₋₈ heterocyclicring in which the heteroatom is selected from the group consisting ofoxygen, nitrogen, and sulfur, or R⁴ and R¹ together with the carbon atomto which they are bonded form an unsubstituted or substituted1,4-benzodioxane, 1,3-benzodioxole, tetrahydronaphthlene,octahydronaphthalene, piperazine, morpholine, tetrahydroquinoline,tetrahydroquinoxaline, tetrahydroisoquinoline; with the proviso that theheterocyclic ring formed by R¹ and R², R² and R³, R¹ and R⁴, or R⁴ andR⁵ is not a five-membered heterocyclic ring in which the heteroatom isoxygen, nitrogen, or sulfur, or six-membered heterocyclic ring in whichthe heteroatom is nitrogen.
 4. The compound of claim 2 of

wherein R¹-R³ are independently hydrogen, an unsubstituted orsubstituted C₁₋₁₂ straight chain alkyl, an unsubstituted or substitutedC₃₋₁₂ branched chain alkyl, an unsubstituted or substituted C₃₋₁₂straight chain olefinic, an unsubstituted or substituted C₃₋₁₂ branchedchain olefinic, a substituted or unsubstituted C₃₋₈ cycloalkyl, asubstituted or unsubstituted C₃₋₈ heterocyclic ring bound through acarbon atom and in which the heteroatom is oxygen or nitrogen, asubstituted or unsubstituted naphthyl, a substituted or unsubstitutedtetrahydronaphthyl, a substituted or unsubstituted octahydronaphthyl,benzyl or substituted benzyl, substituted with up to three substituents,or phenyl or substituted phenyl, substituted with up to threesubstituents; R⁴ is hydrogen, an unsubstituted or substituted C₁₋₁₂straight chain alkyl, an unsubstituted or substituted C₃₋₁₂ branchedchain alkyl, an unsubstituted or substituted C₃₋₁₂ straight chainolefinic, an unsubstituted or substituted C₃₋₁₂ branched chain olefinic,a substituted or unsubstituted benzyl, an unsubstituted or substitutedphenyl, a substituted or unsubstituted piperazino, a substituted orunsubstituted morpholino, amino, an unsubstituted or substitutedalkylamino, an unsubstituted or substituted arylamino, an unsubstitutedor substituted dialkylamino, an unsubstituted or substituteddiarylamino, carboxyalkylamino, carboxydialkylamino, unsubstituted orsubstituted tolyl, xylyl, anisyl, mesityl, an unsubstituted orsubstituted acetyl, an unsubstituted or substituted acetoxy, carboxy, anunsubstituted or substituted carboxymethyl, an unsubstituted orsubstituted carboxyethyl, an unsubstituted or substituted alkylcarbonyl,thiol, an unsubstituted or substituted alkylthio, an unsubstituted orsubstituted alkoxy, carboxamido, an unsubstituted or substitutedalkylcarboxamido, or an unsubstituted or substituted dialkylcarboxamido,an unsubstituted or substituted phenoxy, an unsubstituted or substitutedbenzyloxy, phenylcarbonyl, benzylcarbonyl, an unsubstituted orsubstituted nitrophenyl, trialkylsilyl or nitro; and R¹ and R² togetherwith the nitrogen atoms to which they are bonded form a substituted orunsubstituted C₃₋₈ heterocyclic ring, or R² and R³ together with thenitrogen atom to which they are bonded form a substituted orunsubstituted C₃₋₈ heterocyclic ring, or R¹ and R⁴ together with thenitrogen atom to which R¹ is bonded and with the carbon atom to which R⁴is bonded and with the intervening carbon atom form a substituted orunsubstituted C₂₋₆ heterocyclic ring; with the proviso that theheterocyclic ring formed by R¹ and R², R² and R³, or R¹ and R⁴ is not afive-membered heterocyclic ring in which the heteroatom is oxygen,nitrogen, or sulfur, or six-membered heterocyclic ring in which theheteroatom is nitrogen.
 5. The compound of claim 2 of

wherein R¹-R³ are independently hydrogen, an unsubstituted orsubstituted C₁₋₁₂ straight chain alkyl, an unsubstituted or substitutedC₃₋₁₂ branched chain alkyl, an unsubstituted or substituted C₃₋₁₂straight chain olefinic, an unsubstituted or substituted C₃₋₁₂ branchedchain olefinic, a substituted or unsubstituted C₃₋₈ cycloalkyl, a C₃₋₈heterocyclic ring bound through a carbon atom and in which theheteroatom is oxygen or nitrogen, a substituted or unsubstitutednaphthyl, a substituted or unsubstituted tetrahydronaphthyl, asubstituted or unsubstituted octahydronaphthyl, benzyl or substitutedbenzyl, substituted with up to three substituents, or phenyl orsubstituted phenyl, substituted with up to three substituents; and R¹and R² together with the nitrogen atoms to which they are bonded form asubstituted or unsubstituted C₂₋₈ heterocyclic ring, or R² and R³together with the nitrogen atom to which they are bonded form asubstituted or unsubstituted C₃₋₈ heterocyclic ring; with the provisothat the heterocyclic ring formed by R¹ and R², or R² and R³ is not afive-membered heterocyclic ring in which the heteroatom is oxygen,nitrogen, or sulfur, or six-membered heterocyclic ring in which theheteroatom is nitrogen.
 6. The compound of Formulae I, II or III ofclaim 2 wherein the substituents on the substituted groups are selectedfrom the group consisting of alkoxy, acyloxy, hydroxy, halo, benzyl,acetyl, carboxyl, carboxyalkyl, carboxyalkylamido, carboxydialkylamido,alkylcarbonyl, arylamino, diarylamino, cyano, tolyl, xylyl, mesityl,anisyl, carboxamido, amino, alkylamino, dialkylamino, formyl, dioxane,thiol, alkylthiol, aryl, heteroaryl, or phenoxy, benzyloxy,phenylcarbonyl, benzylcarbonyl, nitrophenyl, trialkylsilyl, nitro,sulfonyl, nitrobenzyl, trialkylammonium, alkyl, cycloalkyl,tetrahydrofuranyl, tetrahydropyranyl, piperidine and morpholine.
 7. Thecompound of claim 3, wherein the substituents on the substituted groupsare selected from the group consisting of alkoxy, acyloxy, hydroxy,halo, benzyl, acetyl, carboxyl, carboxyalkyl, carboxyalkylamido,carboxydialkylamido, alkylcarbonyl, arylamino, diarylamino, cyano,tolyl, xylyl, mesityl, anisyl, carboxamido, amino, alkylamino,dialkylamino, formyl, dioxane, thiol, alkylthiol, aryl, heteroaryl, orphenoxy, benzyloxy, phenylcarbonyl, benzylcarbonyl, nitrophenyl,trialkylsilyl, nitro, sulfonyl, nitrobenzyl, trialkylammonium, alkyl,cycloalkyl, tetrahydrofuranyl, tetrahydropyranyl, piperidine andmorpholine.
 8. The compound of claim 4, wherein the substituents on thesubstituted groups are selected from the group consisting of alkoxy,acyloxy, hydroxy, halo, benzyl, acetyl, carboxyl, carboxyalkyl,carboxyalkylamido, carboxydialkylamido, alkylcarbonyl, arylamino,diarylamino, cyano, tolyl, xylyl, mesityl, anisyl, carboxamido, amino,alkylamino, dialkylamino, formyl, dioxane, thiol, alkylthiol, aryl,heteroaryl, or phenoxy, benzyloxy, phenylcarbonyl, benzylcarbonyl,nitrophenyl, trialkylsilyl, nitro, sulfonyl, nitrobenzyl,trialkylammonium, alkyl, cycloalkyl, tetrahydrofuranyl,tetrahydropyranyl, piperidine and morpholine.
 9. The compound of claim5, wherein the substituents on the substituted groups are selected fromthe group consisting of alkoxy, acyloxy, hydroxy, halo, benzyl, acetyl,carboxyl, carboxyalkyl, carboxyalkylamido, carboxydialkylamido,alkylcarbonyl, arylamino, diarylamino, cyano, tolyl, xylyl, mesityl,anisyl, carboxamido, amino, alkylamino, dialkylamino, formyl, dioxane,thiol, alkylthiol, aryl, heteroaryl, or phenoxy, benzyloxy,phenylcarbonyl, benzylcarbonyl, nitrophenyl, trialkylsilyl, nitro,sulfonyl, nitrobenzyl, trialkylammonium, alkyl, cycloalkyl,tetrahydrofuranyl, tetrahydropyranyl, piperidine and morpholine.
 10. Thecompound of claim 2 of Formulae I, II or III, wherein the substituent onthe substituted groups is a heteroaryl selected from the groupconsisting of pyrrole, furan, thiophene, thiazole, pyrazole, pyran,pyridine, and pyrimidine.
 11. The compound of claim 7, wherein thesubstituent on the substituted groups is a heteroaryl selected from thegroup consisting of pyrrole, furan, thiophene, thiazole, pyrazole,pyran, pyridine, and pyrimidine.
 12. The compound of claim 8, whereinthe substituent on the substituted groups is a heteroaryl selected fromthe group consisting of pyrrole, furan, thiophene, thiazole, pyrazole,pyran, pyridine, and pyrimidine.
 13. The compound of claim 9, whereinthe substituent on the substituted groups is a heteroaryl selected fromthe group consisting of pyrrole, furan, thiophene, thiazole, pyrazole,pyran, pyridine, and pyrimidine.
 14. The compound of claim 2 of FormulaeI, II or III, wherein the substituents on the substituted groups areselected from the group consisting of benzyl, tolyl, carboxyl,carboxyalkyl, dialkylamino, arylamino, and diarylamino.
 15. The compoundof claim 3, wherein the substituents on the substituted groups areselected from the group consisting of benzyl, tolyl, carboxyl,carboxyalkyl, dialkylamino, arylamino, and diarylamino.
 16. The compoundof claim 4, wherein the substituents on the substituted groups areselected from the group consisting of benzyl, tolyl, carboxyl,carboxyalkyl, dialkylamino, arylamino, and diarylamino.
 17. The compoundof claim 5, wherein the substituents on the substituted groups areselected from the group consisting of benzyl, tolyl, carboxyl,carboxyalkyl, dialkylamino, arylamino, and diarylamino.
 18. The compoundof claim 5, wherein R¹ and R² are hydrogen and R³ is the entiresubstituent attached to an amine of a compound selected from the groupconsisting of an amino acid, tryptamine, serotonin, histamine,valcyclovir, adenosine, thyroxine, guanine, guanosine, ubenimex,glucosamine, mannosamine, mycosamine, sphingosine, thienamycin,penicillamine and rimantadine.
 19. The compound of claim 18, wherein theamino acid is selected from the group consisting of lysine, tryptophanand hydroxy-tryptophan.
 20. A compound selected from the groupconsisting of

wherein R¹, R², R⁵ and R⁶ are independently hydrogen, an unsubstitutedor substituted C₁₋₁₂ straight chain alkyl, an unsubstituted orsubstituted C₃₋₁₂ branched chain alkyl, an unsubstituted or substitutedC₃₋₁₂ straight chain olefinic, an unsubstituted or substituted C₃₋₁₂branched chain olefinic, a substituted or unsubstituted benzyl, asubstituted or unsubstituted phenyl, a substituted or unsubstitutedpiperazino, a substituted or unsubstituted morpholino, amino, anunsubstituted or substituted alkylamino, an unsubstituted or substitutedarylamino, an unsubstituted or substituted dialkylamino, anunsubstituted or substituted diarylamino, carboxyalkylamino,carboxydialkylamino, cyano, a substituted or unsubstituted tolyl, xylyl,anisyl, mesityl, an unsubstituted or substituted acetyl, anunsubstituted or substituted acetoxy, carboxy, an unsubstituted orsubstituted carboxymethyl, an unsubstituted or substituted carboxyethyl,an unsubstituted or substituted alkylcarbonyl, thiol, an unsubstitutedor substituted alkylthio, an unsubstituted or substituted alkoxy,carboxamido, anunsubstituted or substituted alkylcarboxamido, or anunsubstituted or substituted dialkylcarboxamido, a substituted orunsubstituted phenoxy, a substituted or unsubstituted benzyloxy,phenylcarbonyl, benzylcarbonyl, a substituted or unsubstitutednitrophenyl, trialkylsilyl or nitro, R¹ and R² together with the carbonto which they are bonded can form a substituted or unsubstituted C⁴-C⁸cycloalkyl, R² and R³ together with the nitrogen atom to which they arebonded form a substituted or unsubstituted C₃₋₈ cycloalkyl, R³ and R⁴are an unsubstituted or substituted C₁₋₁₂ straight chain alkyl, anunsubstituted or substituted C₃₋₁₂ branched chain alkyl, anunsubstituted or substituted C₃₋₁₂ straight chain olefinic, anunsubstituted or substituted C₃₋₁₂ branched chain olefinic, asubstituted or unsubstituted C₃₋₈ cycloalkyl, a substituted orunsubstituted C₃₋₈ heterocyclic ring bound through a carbon atom and inwhich the heteroatom is oxygen or nitrogen, a substituted orunsubstituted naphthyl, a substituted or unsubstitutedtetrahydronaphthyl, a substituted or unsubstituted octahydronaphthyl,benzyl or substituted benzyl, substituted with up to three substituents,or phenyl or substituted phenyl, substituted with up to threesubstituents, or R³ and R⁴ together with the nitrogen atom to which theyare bonded can form a C₃₋₈ heterocyclic ring or a C₃₋₈ substitutedheterocyclic ring or a C₃₋₈ unsubstituted or substituted heterocyclicring containing up to two additional heteroatoms selected from the groupO, S, N, or R¹ and R⁶ together with the C═C—C through which they arebonded form an unsubstituted or substituted cycloalkyl, or R⁵ and R⁶together with the carbon to which they are bonded can form a substitutedor unsubstituted C₄₋₈ cycloalkyl.
 21. A compound of

wherein R¹ and R² are independently hydrogen, an unsubstituted orsubstituted C₁₋₁₂ straight chain alkyl, an unsubstituted or substitutedC₃₋₁₂ branched chain alkyl, an unsubstituted or substituted C₃₋₁₂straight chain olefinic, an unsubstituted or substituted C₃₋₁₂ branchedchain olefinic, a substituted or unsubstituted benzyl, a substituted orunsubstituted phenyl, a substituted or unsubstituted piperazino, asubstituted or unsubstituted morpholino, amino, an unsubstituted orsubstituted alkylamino, an unsubstituted or substituted arylamino, anunsubstituted or substituted dialkylamino, an unsubstituted orsubstituted diarylamino, carboxyalkylamino, carboxydialkylamino, cyano,a substituted or unsubstituted tolyl, xylyl, anisyl, mesityl, anunsubstituted or substituted acetyl, an unsubstituted or substitutedacetoxy, carboxy, an unsubstituted or substituted carboxymethyl, anunsubstituted or substituted carboxyethyl, an unsubstituted orsubstituted alkylcarbonyl, thiol, an unsubstituted or substitutedalkylthio, an unsubstituted or substituted alkoxy, carboxamido, anunsubstituted or substituted alkylcarboxamido, or an unsubstituted orsubstituted dialkylcarboxamido, a substituted or unsubstituted phenoxy,a substituted or unsubstituted benzyloxy, phenylcarbonyl,benzylcarbonyl, a substituted or unsubstituted nitrophenyl,trialkylsilyl or nitro, R³ and R⁴ are an unsubstituted or substitutedC₁₋₁₂ straight chain alkyl, an unsubstituted or substituted C₃₋₁₂branched chain alkyl, an unsubstituted or substituted C₃₋₁₂ straightchain olefinic, an unsubstituted or substituted C₃₋₁₂ branched chainolefinic, a substituted or unsubstituted C₃₋₈ cycloalkyl, a substitutedor unsubstituted C₃₋₈ heterocyclic ring bound through a carbon atom andin which the heteroatom is oxygen or nitrogen, a substituted orunsubstituted naphthyl, a substituted or unsubstitutedtetrahydronaphthyl, a substituted or unsubstituted octahydronaphthyl,benzyl or substituted benzyl, substituted with up to three substituents,or phenyl or substituted phenyl, substituted with up to threesubstituents.
 22. A compound of

wherein R⁵ and R⁶ are independently hydrogen, an unsubstituted orsubstituted C₁₋₁₂ straight chain alkyl, an unsubstituted-or substitutedC₃₋₁₂ branched chain alkyl, an unsubstituted or substituted C₃₋₁₂straight chain olefinic, an unsubstituted or substituted C₃₋₁₂ branchedchain olefinic, a substituted or unsubstituted benzyl, a substituted orunsubstituted phenyl, a substituted or unsubstituted piperazino, asubstituted or unsubstituted morpholino, amino, an unsubstituted orsubstituted alkylamino, an unsubstituted or substituted arylamino, anunsubstituted or substituted dialkylamino, an unsubstituted orsubstituted diarylamino, carboxyalkylamino, carboxydialkylamino, cyano,a substituted or unsubstituted tolyl, xylyl, anisyl, mesityl, anunsubstituted or substituted acetyl, an unsubstituted or substitutedacetoxy, carboxy, an unsubstituted or substituted carboxymethyl, anunsubstituted or substituted carboxyethyl, an unsubstituted orsubstituted alkylcarbonyl, thiol, an unsubstituted or substitutedalkylthio, an unsubstituted or substituted alkoxy, carboxamido, anunsubstituted or substituted alkylcarboxamido, or an unsubstituted orsubstituted dialkylcarboxamido, a substituted or unsubstituted phenoxy,a substituted or unsubstituted benzyloxy, phenylcarbonyl,benzylcarbonyl, a substituted or unsubstituted nitrophenyl,trialkylsilyl or nitro, R³ and R⁴ are an unsubstituted or substitutedC₁₋₁₂ straight chain alkyl, an unsubstituted or substituted C₃₋₁₂branched chain alkyl, an unsubstituted or substituted C₃₋₁₂ straightchain olefinic, an unsubstituted or substituted C₃₋₁₂ branched chainolefinic, a substituted or unsubstituted C₃₋₈ cycloalkyl, a substitutedor unsubstituted C₃₋₈ heterocyclic ring bound through a carbon atom andin which the heteroatom is oxygen or nitrogen, a substituted orunsubstituted naphthyl, a substituted or unsubstitutedtetrahydronaphthyl, a substituted or unsubstituted octahydronaphthyl,benzyl or substituted benzyl, substituted with up to three substituents,or phenyl or substituted phenyl, substituted with up to threesubstituents.
 23. The compound of claim 22, wherein R² and R³, togetherwith the carbon and nitrogen atom to which they are bonded, form a C₃₋₈cycloalkyl.
 24. The compound of claim 23, wherein the C₃₋₈ cycloalkyl issubstituted with a heteroatom.
 25. The compound of claim 22, wherein R⁵and R⁶, together with the C═C—C through which they are bonded, form aC₃₋₁₂ alicyclic hydrocarbon.
 26. The compound of claim 21, wherein R³and R⁴, together with the nitrogen to which they are bonded, form a C₃₋₈cycloalkyl.
 27. The compound of claim 26, wherein the C₃₋₈ cycloalkyl isfurther substituted with an unsubstituted or substituted heteroatom oran aromatic ring, optionally substituted with a C₁₋₆ alkyl or a C₁₋₆alkoxy, and R¹ and R² optionally together form a C₃₋₈ cycloalkyl.
 28. Amethod of treating an animal having a biological disorder treatable withnitric oxide, which method comprises administering to the animal acompound of claim 1 in an amount sufficient to treat the biologicaldisorder in the animal.
 29. A method of preventing a biological disorderin a mammal susceptible to prevention with nitric oxide, which methodcomprises administering to the mammal a compound of claim 1 in an amountsufficient to prevent the biological disorder in the mammal.